[Visualpython-users] 4.beta9 -- faster graphing

[Bruce S. <Bru...@nc...>]

New beta test version 4.beta9 now available for Windows and Linux at 
http://sourceforge.net/projects/visualpython

Changes that handle nonuniform axes for curve, points, faces, and label, 
which makes graphing much faster than it was on 4.beta8. If you try to 
create other objects after establishing nonuniform axes an exception is 
raised. Note that scene.uniform = False was never well supported in the 
past due to the impossibility of displaying (say) an arrow in 3D if the 
scale factors on different axes were different. My impression is that 
nonuniform axes were essentially never used.

The list of "3 serious bugs" has been changed to "2 serious bugs" 
(quitting, and gas.py jerky animation).

The graphing speed for curves (gcurves) is 25 times faster than it was 
with 4.beta8, but still 7 times slower than Visual 3, though I don't 
understand why, since it seems to me that the operations are about the 
same as before. It is gcurve that needs to go as fast as possible. A 
clue is that if you specify xmin, xmax, ymin, ymax (fixed axes), the 
speed is as fast as with Visual 3, which implies that there's something 
different in resetting the scale factors in visual.graph.

The graphing speed for points (gdots) is also 25 times faster than it 
was with 4.beta8, and 5 times faster than Visual 3, where we had to plot 
the letter "o", which was very slow.

My test routine for timing performance is this:

from visual.graph import *
from time import clock
c = gcurve(color=color.yellow)
t = clock()
x = 0
while x < 100:
   c.plot(pos=(x,cos(x)))
   x += 0.01
t = clock()-t
print t

Bruce